Method of making a plastic boot or the like



March 6, 1956 c. E. JOHNSON, JR., l-:TAL 2,736,926

METHOD OF MAKING A PLASTIC BOOT OR THE LIKE Filed Aprill 11, 1952 UnitedStates- Patent() NIETHOD F MAKING A PLASTIC BOOT 0R THE LIKE Clarence E.Johnson, Jr., and Bernhardt M. Pederson, Jr., Winona, Minn., assignorsto Plasti Industries, Inc., Winona, Minn., a corporation of MinnesotaApplication April 11, 1952, Serial No. 281,814

2 Claims. (Cl. 18-58.7)

The present invention relates to an overshoe or boot made of plastic orrubber-like material for the protection of the shoe, foot, and ankle ofthe wearer, and to its method of manufacture.

The primary object of this invention is to provide a new and improvedplastic overshoe or boot with increased wearability and anti-skidproperties.

Another object is to provide a reinforced heel portion in the sole ofthe above-mentioned boot to increase the over-all life and wearresistant properties of the boot. This reinforcing is in the form of afabric pad or mat molded into the sole of the boot during itsmanufacture so that the pad will lie between the upper and lowersurfaces of the boot sole` Another object is to provide a frictional ornon-slip bottom on the sole of the boot to substantially increase itsanti-slip qualities. The bottom of the sole is made up of a collectionof irregular peaks and valleys so as to provide a non-directionalsurface which possesses increased anti-slip characteristics.

Another object is to provide a new and improved method by which thisnon-directional, anti-slip sole on the boot can easily be made.

Other objects will, from time to time, appear in the specifications anddrawings wherein:

Figure 1 is a side elevation, partly in sections, of my new boot;

Figure 2 is a sectional view along line 2 2 of Figure 1 illustrating theupper surface of the boot sole and the reinforcing pad;

Figure 3 is a bottom view of Figure 1 illustrating the lower surface ofthe boot sole with its anti-slip, nondirectional surface;

gigure 4 is a sectional View along line 4-4 of Figure 2; an

Figure 5 is a view of the reinforcing pad that is molded into the soleof the boot heel as shown in Figure 4.

Like parts are indicated by like symbols throughout the specificationsand drawings.

The over-all boot is composed primarily of an upper portion 2 for theprotection of the ankle of the wearer and a lower portion 3 to receivethe foot and shoe of the wearer. The upper portion 2 is provided with anadjustable strap 4 and a buckle 5 for adjusting the strap so that theupper portion of the boot may be manifolded snugly in and around thewearer of the boot. The strap d carries a snap 6 and the buckle 5carries a snap 7 shown in Figure l, these snaps engaging mating parts onthe upper portion 2 of the boot. The snaps on the strap and their matingparts on the upper portion 2 of the boot are appropriately spaced sothat the upper portion 2 of the boot may be readily taken in and let outby the use of the strap. The buckle 5 carrying snap 7 is slideable alongStrap 4 so that the distance between snaps 6 and 7 on the strap may bereadily adjusted to accon.- modate various sizes of ankles.

The lower portion 3 of the boot has an over-all rein- V ice forced crosssection 8 as this portion will be subjected to a great deal more wear bydirect contact with the shoe of the wearer than will the upper portion2. Lower portion 3 is composed primarily of a heel-enclosing section 9,a toe section 10, and two side walls 11 and 12 joining these twosections on each side of the wearers shoe so as to form an enclosedboot. The sole 13 is provided with a thicker cross section than theupper walls of the boot, see Figure 4, to increase the life and wearresistant qualities of the lower portion of the boot.

This type of overshoe is primarily designed for use by women, and thesharp heels of the wearer have proved extremely detrimental to the heelportion of the boot. To resist these sharp heels a reinforced pad or mat14 is molded into the heel portion of the boots sole 13 during itsmanufacture as described hereinbelow so that the pad 14 will lie betweenthe upper and lov er surfaces 15 and 16 of the sole 13 so as to beembedded therein.

The lower surface 16 is provided with a non-directional congurationcomposed of a collection of irregular peaks and valleys so that no setpattern or established plain surface is afforded.

A bow l may be used in connection with the adjustable strap 4 forornamental purposes only, if such a feature is desirable.

This boot is best made by a dipping process. A mold of the proper sizeis rst selected and prepared and then dipped in a dispersion of theplastic in a liquid state. The'mold with a layer of plastic adheringthereto is withdrawn from the liquid solution and allowed to cool untilwhat might be termed a tacky point is reached, then the fabricreinforcement 14 is secured to the heel portion ofthe mold by theapplication of pressure. The mold with the reinforcing pad adheringthereto is again dipped into the dispersion of liquid plastic but thistime the mold is immersed only up to the line 17 in Figure l andwithdrawn after a sufficient coating of plastic has formed around thelower portion of the mold. The mold with the boot adhering thereto isallowed to dry until the lower portion again reaches the so-called tackypoint whereupon an object with numerous bristles, such as a hair brush,is applied to the sole of the boot. The brush engages the sole so thateach bristle becomes lightly covered with plastic on the tip thereof andbecause the plastic is in a tacky condition, it adheres to the bristlesof the brush. Then the brush is pulled away from the sole, portions ofthe material adhering to and moving away with the brush and portionsremaining with the sole so that a roughened nondirectional surfaceremains on the sole of the "boot, This procedure is repeated over theentire sole area until a non-directional, roughened surface covers theentire lower surface i6.

The boot is allowed to dry suiciently on the mold until it is ready forcuring in an oven of approximately 370 Fahrenheit whereupon it is placedin such an oven to be baked for approximately a half an hour so that thecomplete boot is properly set and hardened and then stripped. The timeof baking can obviously be varied according to the characteristics ofthe plastic-like material selected, and if the material does not requirebaking, this step may be eliminated.

hile i have illustrated and described a preferred form of my plasticboot, l do not wish to be understood to confine myself specificallythereto except as limited by the appended claims.

I claim:

l. A method of forming a flexible boot of plastic-like materialcomprising the steps of dipping a boot mold into a liquid solution ofplasticdike material to form a coating of material thereon, removing themold and allowing the coating to dry until it becomes slightly tacky,applying the bristles of a brush-like object to the sole of the coatingso that material will adhere to the bristles, and drawing the objectaway from the coating with portions of the plastic material adheringthereto so that a non-directional anti-slip surface of irregular peaksand valleys will be formed on the sole area.

2. The method of claim 1 characterized by and including the step ofsubjecting the plastic coating to an elevated temperature for apredetermined period of time to harden it.

References Cited in the ile of this patent UNITED STATES PATENTS ClarkJune 29, Grosky July 28, Miller Nov. 10, Murphy May 9, McCandlish Jan.26, Demick Dec. 26,

FOREIGN PATENTS Great Britain Feb. 5,

Great Britain Mar. 25,

